(a) Field
The invention relates to a lens for a backlight of a display device, and a backlight of a display device including the same. More particularly, the invention relates to a lens for a backlight of a display device in which color separation and color blurring are reduced or effectively prevented, and a backlight of a display device including the same.
(b) Description of the Related Art
Display devices are employed in a computer monitor, a television, a mobile phone and the like which are widely used electronic display devices. The display devices include a cathode ray tube display device, a liquid crystal display, a plasma display device, and the like.
The liquid crystal display, which is one of the most common types of flat panel displays, includes two display panels in which field generating electrodes such as a pixel electrode and a common electrode are disposed, and a liquid crystal layer that is interposed between the two display panels. The liquid crystal display generates an electric field in the liquid crystal layer by applying voltages to the field generating electrodes, and determines the orientation of liquid crystal molecules of the liquid crystal layer by the generated electric field, thus controlling polarization of incident light so as to display images.
Such a liquid crystal display is not self-emissive, and therefore the liquid crystal display employs a backlight including a light source to generate light. The light source may be an additionally provided artificial light source and/or natural light. An artificial light source used in the liquid crystal display may include a light emitting diode (“LED”), a cold cathode fluorescent lamp (“CCFL”) and an external electrode fluorescent lamp (“EEFL”).
To improve color reproducibility of the backlight, a technique of disposing a plurality of LED chips as one package has been used. However, the light of different colors emitted from the plurality of LED chips are separated such that a color separation phenomena in which the light is emitted and separated may be generated, and as a result, color blurring may occur.